Lens grinding machine



NOV. 9, 1948. E. BONlN 2,453,300

LENS GRINDING MACHINE Filed Sept. 18, 1946 4 Shets-Sheet 1 1943- e. E. BONIN LENS GRINDING MACHINE 4 Sheets-Sheet 3 Filed Sept. 18, 1946 [NVEN TOR. 660296 5 m'n BY 62. 'f

Nov. 9, 1948..

Filed Sept. 18, 1946 G. E. BONIN LENS GRINDING MACHINE 4 Sheets-Sheet 4 w J ll! INVENTOR. 6230296 5.130724%?) aw; q

Patented Nov. 9, 1948 i 25453300 I Y 1 r IJENS 'GRINDING MACHINE George Bonim-S'outhbridge, Mass., assignor-to 'Siin'onds :Machine '00., Inc, S'outhbridge;.Ma'ss. 'aoor-poration: of Massachusetts. 'Applicatiowse teniber 18, IB LSfS'eriRINo. 697:701

. .1: Thisinventmnrelates tea-machine for grind ing or lap in optical 'lensespr other similar prciiutts having segmental spherical concave or convex surfaces.

*it is'tustomary *in-su'cn-macmrres to provide a l'a'p"-vv hich is the '1 e'ci'procal of' thede'siredcontour and-a workpiece "which 'is shaped to v the "desired 'c'ontbur; "The work and-"lap arethenrelatively reciprocated under ressure and With'a suitable grinding compound until the work i's given the reciprocal contour ofthe lap;

'itf is tl'l general objectof my invention"to prov iiiiprovedmechanism for effecting such relative motions of-the work and lap" so that "a very accurate grinding operation may "be I more rapidly performed.

To the -accomp1ishment"or this "general object,

I provide means for reeipl'ocatingthelap' in one direction and means for reciprocating the work in atrafisvelse' direction. *Ifals'o provide 'means for transversely shifting the lo'cu's "of the trans.- verse reciprocation; and means for; -applying. any desired pressure to the work during the grinding cperation. '-'I alsomou'n't the workin'such'ma'nner that it may beeasily released for inspection 'or replacement.

- My invention further relates to "arrangements and combinations: of. parts which "wilfb'e hereinafter"describ'e'cl andmore particularly pointed out in the appended claims.

A preferred form of the invention is shown in the drawings, in which Fig, 1 is a plan view of my improved machine;

Fig. 2 is aside elevation thereof;

Fig. 3 is a front elevation thereof, partly broken away;

Figzf l is a front eleva-tien of a g'ear box forming part of my improved machine; and

*Fig; -5 is' a left-hand sectionalside elevation, taken' alon'g the irregular 'lin'e "-5 in Fig. '4.

The operating 'parts of the machine. .are mounted ona baseB "(Fig 2) having ..a hinged cover 4 'C which "may "be manually lifted" and may be supported in raised position by a brace 9.

Referring particularly to Fig. 2, the lens or similar workpiece W is cemented or otherwise secured to a block 10 which is engaged by a pair of pointed studs I2 (Fig. 3) which are clamped in a rocker M (Fig. 2) pivoted on studs IS in depending arms I! forming part of a work-shifting head 20.

The lower surface of the work W engages a lap which may be concave as shown at L in Fig. 2 or convex as shown at L in Fig. 3, according to SFGlaims. (Cl; 55 E 64 2 whetheraconvex or concave reciprocal 'fir'iished surface is to be produced on the work. The lap-L or L is-"m'ounted on aforwariily projecting portion 22' 'of a carriage "C an'd' maybe clamp'etitheleo'n -by{ a-do'g "23 *(Fig. 2) which ma be tightened againstth'e lap -by'"-turn'ing-a' hand wheel 25. The rear portion 38 (Fig; men-the carriage C extends through "a' longitudinal slot 3"! in the front'wall '32-'-of"the-inachine"casing*aird the carriage portion '30 is providedwith'a'pluraL ity of rolls "33. The portion 30- is elongated'and has'a-setofthe 'rolls"33 at ea'c'h'en'd; which -rolls engage a fiXedguide-ba'r'3'5 .on't'h'e'top and'bo't'tom surfaces thereof and on the front *an'dr'earedges carriage-C isthus firmlysupported for longifa tudinal reciprocation "during" the grinding oper ation.

'Recipr'ocatingmotion of: the carriageiC produ'cedbyfa' link 40 "(Fig. 3) iconnectedtat" one end tothe carriage "O'and at the'ot'heren'd to'a crarik-arm "42' (Figs. an-d3) mou'nted'on a crankshaft 43. rotataiile in fikedbearin'gs an'd providedwith a grooved pulley *44. .AxV "belt 65 '(Fig; 1') connects thefipu'lley 4' 5 withqa'fdriving pulley-4'6 'a'tt'he rear of" agear 'box'Gshownin detail in'Figs. l'an'd 5"andtobe later described. In the preferred-form o'f my'improvcd machine, provision is m'ade'for grinding two lenses atxthe same-time, and the lap-supporting, carriageC is duplicated, as, is also the work-supporting, and worka'shiftin'g'mechanism; but a' description of one set of these parts will be understood to. apply equally to thesecondset. Q

"Workeshzftmg "mechanism 1 Each workesupporting: head Z i3; forms-a depending part .of ashiftingmember 60- (-Fig. 2); to which upper and-loweractuating links 61 and 62 are pivoted at -i'i3nand 84. The upperelinkmlil is of open .or yokeform as best-.showniin Fig, -1 and has eccentric .beari-ngsili' (Fig 2) on .an operat: ing shaftlfl'. The.lowerlink-.6Zhaeacorrespond ing eccentric bearing 68 on an operating shaft 69. Actuating mechanism to be described rotates the shaft 61 relatively slowly and the shaft 69 at relatively high speed.

The work W is thus given a short rapid forward-and-back motion in rocking engagement with the lap L or L. The locus of this rapid reciprocation is slowly moved forward and rearward by the upper link 6! which is shifted by the slow-speed eccentric shaft 67.

At the same time the carriage C is being shifted longitudinally of the guide-bar 35 (or traversely 3 relative to the work) so that the combined effect is to move the work W over the lap L or L in a constantly shifting path.

Driving mechanism The various moving parts of my improved machine are actuated from a single motor M (Fig. 1) by means of a V-belt connecting a driving pulley H on the motor armature shaft 72 toa driven pulley 13 mounted on the front of the gear box G. Double pulleys may be provided if desired, so that the speed relation between the motor M and the mechanism in the gear box G may be increased or decreased.

The pulley '13 (Fig. 2) is mounted 'on a shaft 16 supported in bearings at the front of the gear box G. The shaft 16 is connected by a pinion ll,

idle gear 18 and gear 19 to the fast eccentric shaft 69. The shaft 69 is connected by a worm 80 (Figs. 4 and 5), worm gear 8|, worm shaft 82, worm 83- and worm gear 84 to the slow-speed eccentric shaft 61.

Asecond worm 86 (Fig. 4) on the shaft 69 engages a worm gear 83 mounted on a shaft89 which supports the driving pulley 46 previously described and through which the carriage C is reciprocated. d f

The desired. motions and speed relations are thus provided for the longitudinal reciprocation of the carriage C for the rapid transverse reciprocation of the work on the lap, and for the slow shifting of the locus of th rapid reciprocation.

Special provision is made for varying the pressure of the work on the lap. For this purpose, a rod 99 (Fig. 2) for each grinding unit is connected at 9| to arms 92 mountedon a shaft S pivoted above the gear box G. The lower end of each rod 90 extends freely through a bearing in a stud 93 mounted in depending lugs 93a on the asso ciated link 6 I. A nut 94 is threaded on the upper part of the rod 90 and a spring 95 is interposed between the nut 94 and a washer 96 which engages the stud 93. A collar 91 is fast on the lower end of the rod 90.. Arms I00 (Figs. 2 and 3) are attached to each shaft S and each arm I00 has a holding latch HH. By unlatching and swinging the arms I00 forward, the collars 9'! may be drawn back against the studs 93. Further movement raises the work-actuating structure.

Downward pressure is thus applied by the spring 95 to the outer or swinging end of the link GI and this pressure is communicated through connecting parts to the work W. The pressure may be varied by adjusting the nut 94 on the threaded rod 99.

Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what I claim is: V,

1. In a lens grinding machine having a Workengaging member and a lap, in combination, a carriage for said lap, a guide-bar, means to reciprocate said carriage along said guide-bar, a depending work-actuating member mounted on 4 upper and lower shiftable pivots, and means t give the work a compound transverse reciprocating movement by moving one of said pivots to rapidly reciprocate said work transversely of the path of movement of the lap and by moving the other pivot to slowl shift the locus of the path of reciprocating movement of the work during such rapid reciprocation transversely of said path of movement of the lap while maintaining the length of said transverse reciprocating move- .ments substantially constant.

2. In a lens grinding machine having a work actuating member and a lap, in combination, a carriage for said lap, a guide-bar, means to reciprocate said carriage along said guide-bar, a depending work-actuating member mounted on upper and lower shiftable pivots, a pair of links pivoted at vertically spaced points to said workactuating member, eccentric bearings for the other ends of said links, and means to give said work-actuating member a compound transverse reciprocating movement by rotating one eccentric relatively rapidly and the other eccentric relatively slowly.

3. The combination in a lens grinding machine as set forth in claim 2, in which a spring applies downward pressure to the work-actuating member and work, and in which means is provided to vary the operative effect of said spring.

4. The combination in a lens grinding machine as set forth in claim 2, in which .a spring applies downward pressure to the work-actuating member and work, and in which means is provided to release said spring pressure and to raise said work-actuating member out of operating position.

5. In a lens grinding machine having a lap, in combination, a work-actuating member, parallel links supporting said member and pivoted to said member at upper and intermediate points, means to reciprocate one link endwise relatively rapidly to shift the work transversely of the lap, means to reciprocate the other link endwise relatively slowly to shift the locus of the path of reciproeating movement of the work during such rapid transverse reciprocation while maintaining the length of-said transverse reciprocation substantially constant, and means to apply controlled downward pressure to said actuating member.

GEORGE E. BONIN.

, REFERENCES CITED The following references are of recordin the file of this patent:

UNITED STATES PATENTS 

